A makeshift piezo earphone arrangement comprises a stethoscope and a piezo transducer.
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Stethoscope |
The sound emanating from the transducer is captured by the bell of the stethoscope, held against its face.
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Piezo Transducer |
This arrangement was recently used to figure out
how to interface a piezo earpiece with a crystal radio. The transducer, a 1¾" telephone ringer, was salvaged from the junk box.
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